Safety cap for medicine containers and the like

ABSTRACT

A safety cap for protecting children from contact with the contents of medicine bottles or containers of poison features a screw-threaded cap on the neck of a bottle or container which cannot be completely removed until an associated plunger is depressed to cause releasing of a locking means in the neck of the bottle or other container.

llnited States Merris SAFETY CAP FOR MEDICINE CONTAINERS AND THE LIKE[76] Inventor: Glenn 1111. Morris, 4203 Highwoocl Drive, Chattanooga,Tenn.

22 Filed: Mar. 14, 1972 21 Appl. No.: 234,507

[52] US. Cl ..215/9 [51] lint. Cl. ..B65d 55/02 [58] Field 011' Search..215/9, 52, 49

[56] References Cited UNITED STATES PATENTS 3,181,718 5/1965 Chancellor..215/9 [4 May29,119'73 Turner ..215/9 Simons ..215/9 PrimaryExaminer-George T. Hall Attorney-Rupert J. Brady, James G. OBoyle andWilliam L. Gates [5 7 ABSTRACT A safety cap for protecting children fromcontact with the contents of medicine bottles or containers of poisonfeatures a screw-threaded cap on the neck of a bottle or container whichcannot be completely removed until an associated plunger is depressed tocause releasing of a locking means in the neck of the bottle or othercontainer.

15 Claims, 11 Drawing Figures PATENTEBHAYZS I975 sum 1 [1F 2 BACKGROUNDOF THE INVENTION There is a recognized need for a simple, reliable andreasonably economical safety closure for medicine and poison containersincluding such common household medicines as aspirin tablets, bloodpressure pills and tranquilizers. As the use of such drugs by adultscontinues to increase, it is more and more vital to protect youngchildren from contact with the same. While this need has been recognizedfor some time and certain proposals to satisfy the need have been madein the prior art, the need has become much more urgent recently in viewof certain Government regulations pertaining to medicine containers andclosures for such containers expected to come into being in the verynear future.

With the above in mind, the objective of this invention is to provide apractical, reliable and economical safety cap of the above type whichwill be sufliciently difficult to remove from the medicine container toconfuse young children so that they will cease in their efforts to openthe container and will thus be protected from harm. At the same time,the container closure will be sufficiently simple to operate by adultsso as not to seriously impede access to the medicine in the container inthe event of an urgent need for such medicine.

Basically, the safety closure embodying the invention comprises ascrew-threaded cap for engagement over exterior screw-threads on theneck or outlet of the container, and an internal axially movablespring-urged locking plunger on the cap including a part capable ofhaving positive locking engagement with projections on the interior ofthe container neck so as to resist complete removal of the cap from thecontainer except when the plunger is properly depressed to overcome theforce of the spring and to be displaced away from said projections.

The safety closure possesses a number of additional features andadvantages over the prior art which will become apparent during thecourse of the following detailed description.

BRIEF DESCRIPTION OF DRAWING FIGURES FIG. I is a central verticalsection taken through a safety cap for medicine containers and the likeembodying the invention, the cap being shown in the completely closedposition on the container.

FIG. 2 is a horizontal section taken on line 2-2 of FIG. 1.

FIG. 3 is a similar section taken on line 3--3 of FIG. I.

FIG. 4 is a sectional view, similar to FIG. I, showing the safety cap ina locked position preventing its complete removal from the container.

FIG. 5 is a similar view showing the locking plunger depressed torelease the screw-threaded cap for further turning in order tocompletely remove the cap.

FIG. 6 is a similar view depicting how the safety cap is completelyseparated from the container by an axial movement.

FIG. 7 is a central vertical cross section taken through a cap andcontainer in accordance with a moditication of the invention.

FIG. 8 is a horizontal section taken on line 3-8 of FIG. 7.

FIG. 9 is a similar section taken on line 9-9 of FIG. 7.

FIG. 19 is an exploded cross sectional view through the safety closureshown in FIG. 7.

FIG. II is a central vertical section showing the cap or closureconditioned for release from the container by depression of the plungermeans.

DETAILED DESCWON OF PREFERRED EWODWIENTS Referring first to FIGS. Ithrough 6 showing one embodiment of the invention, wherein like numeralsdesignate like parts, the numeral 29 designates the neck of a medicinebottle or the like, such as a bottle for aspirin tablets. The form ofthe invention shown in FIGS. 1-6 is particularly suitable for aspirin orother pill containers. The container neck 20 is formed with externalscrew-threads 21 near its open end and a plurality of circumferentiallyequidistantly spaced locking lugs or projections 22 is formed on theinterior of the neck 29 near and below its open end and projectingradially into the bore or outlet passage of the neck. While eight of theprojections 22 are shown, a lesser number may be employed in someinstances but at least two locking projections will always be requiredfor proper operation of the safety cap.

The invention further comprises an internally screwthreaded closure cap23 adapted to be applied over the screw-threads 21 by turning in theusual manner. The cap 23 is illustrated as a metal cap but a moldedplastic cap or bakelite cap is also suitable for use in the invention.Above the screw-threaded skirt 24 of the cap 23, a right angular annularshoulder 25 opposes the end of the bottle neck 29 and a suitablecompressible gasket 26 is preferably provided on this shoulder to sealthe mouth of the container when the cap 23 is fully closed. The cap 23further comprises an elevated cylindrical crown portion 27 of somewhatreduced diameter including a top wall 28 spaced substantially above theshoulder 25 and the open end of the bottle neck.

F ixedly secured within the crown portion 27 is a cuplike element 29,open at the top and having a lower end wall 39 flush with the shoulder25. Relative rotation be tween the cup 29 and cap 23 is prevented bycrimping the side wall of the crown portion 27 as at 311, FIG. 3, intorecesses formed at the same location in the cup 29. The interior of thecup 29 is provided with a plurality of splines or keyways 32 extendingfrom the open top of the cup down to the wall 39.

The safety cap additionally comprises a plunger assembly which includesa central axial pin or shaft 33, the upper end of which extends slidablythrough a central opening 34 in the top wall 28 of the cap crownportion. The upper end of the pin 33 is thus positioned conveniently tobe depressed axially by the thumb or finger of the user. The plungerassembly further comprises a splined disc 35 on the pin 33 and rigidtherewith. The marginal teeth or splines of this disc are receivedslidably in the keyways 32 so as to allow ready reciprocation of theplunger assembly while preventing rotation thereof relative to the cup29 and cap 23. The plunger assembly further comprises a lower pin orshaft section 36 separate from the section 33 and coupled therewiththrough a square projection 3'7 on the lower end of pin section 33 whichis received snugly in a square socket opening 33 formed in the upper endof secnon 36 of the plunger pin or shaft. The components 37 and 38 maybe press-fitted or adhesively secured in assembled relationship.

The lower end of pin section 36, FIG. 1, extends below the lockingprojections 22 when the plunger assembly is elevated and a rigidtransverse locking bar 39 is fixedly secured to the lower end of theextension 36 by any suitable means and extends equidistantly radially onopposite sides of the plunger pin or shaft. The length of the lockingbar 39 is slightly less than the bore diameter of the neck 20 so thatthe bar 39 may revolve within the bore with slight radial clearance asshown in FIG. 2. The projections 22 are of a sufficient size to blockupward movement of the bar 39 with the plunger assembly when the bar ispositioned to interfere with a pair of the projections as illustrated inFIG. 2. However, there is sufficient circumferential space between eachpair of projections 22 to allow the bar 39 to pass upwardly whenproperly oriented relative to the locking projections 22, as illustratedin FIG. 6.

The plunger assembly further includes on the pin section 36 a radiallyprojecting annular seal 40 adapted to abut the lower face of cup wall 30so as to form a seal around the central opening 41 which receives theplunger shaft slidably. The entire plunger assembly is biased upwardlyby a compressible coil spring 42 held within the cup 29 and having itstop end engaging the splined disc 35. This spring maintains positivecontact between the seal 40 and the cup wall 30 except when the plungerassembly is depressed manually relative to the cup and threaded cap 23.A sufficient clearance space 43 is provided between the cap top wall 28and disc 35 to assure proper seating of the seal 40 under influence ofthe spring.

The mode of operation of the safety cap can be readily understood byreference to FIGS. 1 and 4 through 6. FIG. 1 shows the cap 23 fullyapplied to the container with the sealing gasket 26 under compressionand the reciprocatory plunger assembly elevated by the spring 42 so thatthe seal 40 is seated against the cup wall 30. The locking bar 39 is nowspaced considerably below the lugs 22.

In the particular embodiment illustrated, it requires two full turns ofthe cap 23 to separate the threaded cap from the neck of the container.This factor is a variable in the invention as is the length of theplunger pin 33-36 establishing the spacing of the bar 39 from theprojections 22 in FIG. 1. In the illustrated arrangement, it is believedthat it will be more confusing and frustrating to a young child to beable to partially remove the cap and then find it locked againstcomplete removal in comparison to having the cap positively lockedinitially. However, it is entirely possible to construct the inventionas shown in FIGS. 1-6 so that a lesser amount of turning of the cap 23is required to separate it from the container and also the locking bar39 can be positioned so that the cap will be locked with respect to thelugs or projections 22 when the cap is fully closed, FIG. 1.

It requires approximately three-fourths of a turn to one turn of the cap23 to elevate the bar 39 into interfering or locking engagement with apair of the lugs 22, as indicated in FIG. 4. Remembering that the cap 23is locked at 31 to the cup 29 and the cup is locked or splined to thedisc 35 of the plunger assembly, there can be no further rotation of thecap assembly in FIG. 4 without first depressing the plunger assembly andtherefore the child is unable to completely separate the threaded capfrom the threaded container by turning the cap and the child will notrealize that a second nonrotary operafion is required to release thecap.

An adult, on the other hand, after turning the cap to the lockedposition of FIG. 4 will merely depress the top of the pin section 33 ofthe plunger assembly against the force of spring 42, FIG. 5, and thiswill shift the locking bar 39 downwardly in the neck of the container toan elevation sufiiciently below the lugs 22 to allow cap 23 to be turnedthe remaining 1% turns, approximately, necessary to completely separatethe threaded cap from the threaded container. When the threaded cap isthus released from the container, the user simply manipulates the capassembly until the locking bar 39 finds a location between pairs of thelugs 22 where it can be elevated with respect to the lugs 22 andcompletely removed from the neck of the container by an axial movement,as depicted in FIG. 6.

To reapply the safety cap to the container, it is necessary to hold theplunger assembly in the depressed position, FIG. 5, and to insert thelocking bar 39 below the lugs 22 and to continue holding the plungerassembly depressed relative to the cap during at least the first 1%turns of the threaded cap onto the threaded neck of the container. Thiswill bring the parts back to their relative positions shownapproximately in FIG. 4 where it is no longer necessary to depress theplunger assembly and the cap may be turned down to its fully closedposition of FIG. 1.

In FIGS. 7 through 11, there is shown a modification of the inventionwhich embodies the same general principle of operation but which issomewhat more compact in construction and requires only a single turn ofthe cap to release the same from the container. Also, in themodification, the cap is locked against release turning from the start.

Referring to FIGS. 7 through 11, a container neck 44 has externalscrew-threads 45 which are engaged by the internal screw-threads of acap 46 which is preferably serrated as shown at 47. Above thescrew-threads of the cap 46, an internal annular shoulder 48 is formedto abut the open end of the container neck. A suitable sealing gasket 49is also provided at this point. Above the shoulder 48, the cap 46 may beexternally tapered at 50 and the upper end of the cap has an openingdefined by a conically tapered bore portion 51 leading to a cylindricalbore 52. Immediately below the bore portion 52, the cap has an internalshallow groove 53, the peripheral wall 54 of which is conically taperedupwardly. At diametrically opposite points, the cap is further providedwith internal locking recesses 55 which intersect the annular groove 53and extend below the same so as to open through the annular shoulder 48,FIG. 10.

The safety cap further embodies a plunger assembly 56 which is movableaxially relative to the cap 46 but locked against rotation relative tothe cap, as will be described. The plunger assembly comprises apreferably square shaft 57 having rigidly secured to its top end aconcave push button 58 having a conical peripheral edge 59 for seatingagainst the conical bore 51, FIG. 7. A gear-like locking disc 60 has acenter square opening 61 formed through its hub receiving the lower endof the shaft 57 and attached thereto by a cross pin 62 which entersregistering openings 63 and 64 of the shaft 57 and locking disc 60. Theperiphery of the locking disc 60 has plural circumferentiallyequidistantly spaced splines or teeth 65 for interlocking engagementbetween internal projections or lugs 66 formed in the container neck atthe mouth of the neck. The diameter of the disc 66 is such that it willeasily enter the bore of the neck with some clearance. The spacing ofthe teeth 65 and lugs 66 is such that when proper alignment is obtained,as shown in FIG. 9, the locking disc 66 can be withdrawn axially fromthe container neck. However, the interengagement of the teeth and lugswill prevent rotation of the disc 60 relative to the container. Asdescribed above, the plunger assembly 56 is a unit consisting of theelements 57, 55, 66 and 62.

in order to lock the plunger assembly 56 against rotation relative tothe threaded cap an additional disc or plate element 67 is providedhaving a conically tapered peripheral edge 68 which aids the disc insnapping readily into the groove 53. The disc 67 has two diametricallyopposite radial detent elements 69 which enter the locking recesses 55to lock the disc 67 against rotation when seated in the groove 53. Thedisc 67 has a center square opening 70 receiving the square shaft 57 andlocking it against rotation relative to the disc 67 and cap Thus it maybe seen that the entire plunger assembly 56 is held against rotationrelative to the cap 416 by the disc 67 and associated elements and thedisc 66 locks the cap 416 and plunger assembly against rotation relativeto the container neck when the teeth 65 and projections 66 areinterengaged, as shown in FIGS. 7 and 9.

In order to maintain the plunger assembly 56 normally elevated and inthe locking position relative to lugs 66, a preferably conical coilspring 71 is interposed between the concave push button or plate 58 andthe locking disc 67 which is fixed in the groove 53. Due to the bevelednature of the periphery of disc 67 and the corresponding taper of thegroove at 56, there is never any tendency for the disc to disengage thegroove 53 when the plunger assembly is depressed, because any flexure ofthe disc 67 will only tend to seat it more firmly in the groove.

The hub of locking disc 66' has an annular groove 72 in its top faceadapted to receive an O-ring seal 73 which forms a seal with the bottomface of disc 67 surrounding the square shaft 57 when the plungerassembly is in the up or locked position.

Referring to FIG. 7, with the parts arranged as shown, the cap 46 whenfully closed is locked against rotation from the beginning by theinterengagement of teeth 65 and lugs 66 and the cap cannot be turned foropening the container without first depressing the plunger assembly 56.Full depression of the plunger assembly 56 to allow opening of thecontainer is illustrated in FIG. lll. This can easily be accomplished bythe thumb or finger of an adult but would be difiicult for smallchildren and very confusing. The locking disc 60 is now shifteddownwardly and out of engagement with the fixed locking lugs 66 of thecontainer neck and the entire safety cap assembly can now be turned thenecessary amount, approximately one full turn in the illustratedembodiment, to completely separate the cap 66 from the container. Whenthe screw-threads are completely separated, the toothed disc 66 can beremoved from the neck of the container by a simple axial liftingmovement, the teeth 65 passing through the spaces between the lugs 66.To reapply the safety cap to the container, the plunger assembly 56 isheld depressed until the cap is screwed onto the container and is thenreleased to re-establish the locked condition shown in FIG. 7.

The terms and expressions which have been employed herein are used asterms of description and not of limitation, and there is no intention,in the use of such terms and expressions, of excluding any equivalentsof the features shown and described or portions thereof but it isrecogiized that various modifications are possible within the scope ofthe invention claimed.

I claim:

l. A safety closure for medicine containers and the like comprising ascrew-threaded closure cap engageable with external threads on acontainer, said container having internal locking projections, areciprocatory locking plunger unit for the safety closure movableaxially relative to said closure cap but held against r0tation relativethereto, said plunger unit having a manually depressable part at the topof the cap and having a rigid locking part at the bottom of the plungerunit entering the container, said rigid locking part adapted tointerlock with said internal projections of the container to resistrotation of the closure cap and plunger unit relative to the container,and a spring engaging the plunger unit and holding it in an undepressedposition relative to said closure cap.

2. The structure of claim l, and a first means locking said plunger unitagainst rotation relative to the closure cap, and a second means on saidplunger unit engageable with said internal locking projections andlocking the plunger unit against rotation relative to said container.

3. The structure of claim 2, and said first means comprising a disc onthe plunger unit movable therewith and having splined engagement with aninterior part of the closure cap, and the second means comprising atransverse member on the lower end of the plunger unit and extendinginto the neck of the container and being rotatable and axially movabletherein when disengaged from said internal projections.

The structure of claim 3, and said closure cap including an elevatedcrown portion above the mouth of said container forming a housing forsaid disc and said spring, said spring bearing on the bottom of saiddisc and urging said plunger unit outwardly relative to the containermouth, said crown portion having an opening rendering the top of theplunger unit accessible for manually depressing said unit against theforce of said spring.

5. The structure of claim 4, and a cup element in the interior of saidcrown portion and secured therein against rotation and having a splinedbore slidably receiving the splined disc for axial movement, the cupelement having a bottom wall forming a support for one end of saidspring, and a seal carried by the plunger unit and having sealingengagement with said bottom wall when the plunger unit is in its normaloutward position under the biasing influence of said spring.

6. The structure of claim 2, and said first means com prising aninternal transverse member locked to said closure cap and held againstrotation relative to the cap and slidably engaging the plunger unit toallow axial reciprocation thereof while locking the plunger unit againstrotation relative to the closure cap, said second means comprisinganother member on the lower end of the plunger unit extendingtransversely thereof and being disposed in the neck of the container andbeing rotatable therein with said cap when released from engagement withsaid internal projections by depression of said plunger unit.

7. The structure of claim 6, and said internal transverse member lockedto said closure cap comprising a disc seated in an internal groove ofthe closure cap and held against rotation in said groove, said dischaving an opening with at least one straight edge portion, and theplunger unit including a shaft member received slidably by said discopening and having the same cross sectional shape as the disc opening,whereby the shaft member is movable axially in said opening but isnonrotatable therein.

8. The structure of claim 7, and a push button element on the top end ofsaid shaft member engageable manually for depressing said plunger unit,said closure cap having a top opening adjacent the push button element,and a compression spring mounted inside of the closure cap between thepush button element and said disc, said spring serving to maintain saidanother member on the lower end of the plunger unit in interlockingengagement with said internal projections but releasable therefrom bymanual depression of the plunger unit.

9. The structure of claim 6, and said second means comprising a tootheddisc on the lower end of the plunger unit and the teeth of said dischaving circumferential interfitting engagement with said internalprojections of the container.

10. The structure of claim 9, and said internal projections comprising aplurality of circumferentially equidistantly spaced teeth-likeprojections in the bore of the container neck substantially at the mouthof said neck.

11. The structure of claim 8, and said push button element comprising adepressed concave plate element having a conical periphery, said caphaving a conical bore portion opening through its top and forming a seatfor said push button element.

12. The structure of claim 1, and said closure cap having an annularlateral shoulder above the screwthreads of the cap adapted to abut theopen end of the container when the cap is completely engaged therewith.

13. The structure of claim 2, and said first means comprising a disc onthe plunger unit movable therewith and having axial moving engagementwith an interior part of the closure cap, and the second meanscomprising a transverse member on the lower end of the plunger unit andextending into the neck of the container and being rotatable and axiallymovable therein when disengaged from said internal projections.

14. The structure of claim 13, and said closure cap including anelevated crown portion above the mouth of said container forming ahousing for said disc and said spring, said spring bearing on the bottomof said disc and urging said plunger unit outwardly relative to thecontainer mouth.

15. The structure of claim 14, and a cup element in the interior of saidcrown portion and secured therein against rotation and having a splinedbore slidably receiving the disc for axial movement, the cup elementhaving a bottom wall forming a support for one end of said spring, and aseal carried by the plunger unit and having sealing engagement with saidbottom wall when the plunger unit is in its normal outward positionunder the biasing influence of said spring.

1. A safety closure for medicine containers and the like comprising ascrew-threaded closure cap engageable with external threads on acontainer, said container having internal locking projections, areciprocatory locking plunger unit for the safety closure movableaxially relative to said closure cap but held against rotation relativethereto, said plunger unit having a manually depressable part at the topof the cap and having a rigid locking part at the bottom of the plungerunit entering the container, said rigid locking part adapted tointerlock with said internal projections of the container to resistrotation of the closure cap and plunger unit relative to the container,and a spring engaging the plunger unit and holding it in an undepressedposition relative to said closure cap.
 2. The structure of claim 1, anda first means locking said plunger unit against rotation relative to theclosure cap, and a second means on said plunger unit engageable withsaid internal locking projections and locking the plunger unit againstrotation relative to said container.
 3. The structure of claim 2, andsaid first means comprising a disc on the plunger unit movable therewithand having splined engagement with an interior part of the closure cap,and the second means comprising a transverse member on the lower end ofthe plunger unit and extending into the neck of the container and beingrotatable and axially movable therein when disengaged from said internalprojections.
 4. The structure of claim 3, and said closure cap includingan elevated crown portion above the mouth of said container forming ahousing for said disc and said spring, said spring bearing on the bottomof said disc and urging said plunger unit outWardly relative to thecontainer mouth, said crown portion having an opening rendering the topof the plunger unit accessible for manually depressing said unit againstthe force of said spring.
 5. The structure of claim 4, and a cup elementin the interior of said crown portion and secured therein againstrotation and having a splined bore slidably receiving the splined discfor axial movement, the cup element having a bottom wall forming asupport for one end of said spring, and a seal carried by the plungerunit and having sealing engagement with said bottom wall when theplunger unit is in its normal outward position under the biasinginfluence of said spring.
 6. The structure of claim 2, and said firstmeans comprising an internal transverse member locked to said closurecap and held against rotation relative to the cap and slidably engagingthe plunger unit to allow axial reciprocation thereof while locking theplunger unit against rotation relative to the closure cap, said secondmeans comprising another member on the lower end of the plunger unitextending transversely thereof and being disposed in the neck of thecontainer and being rotatable therein with said cap when released fromengagement with said internal projections by depression of said plungerunit.
 7. The structure of claim 6, and said internal transverse memberlocked to said closure cap comprising a disc seated in an internalgroove of the closure cap and held against rotation in said groove, saiddisc having an opening with at least one straight edge portion, and theplunger unit including a shaft member received slidably by said discopening and having the same cross sectional shape as the disc opening,whereby the shaft member is movable axially in said opening but isnon-rotatable therein.
 8. The structure of claim 7, and a push buttonelement on the top end of said shaft member engageable manually fordepressing said plunger unit, said closure cap having a top openingadjacent the push button element, and a compression spring mountedinside of the closure cap between the push button element and said disc,said spring serving to maintain said another member on the lower end ofthe plunger unit in interlocking engagement with said internalprojections but releasable therefrom by manual depression of the plungerunit.
 9. The structure of claim 6, and said second means comprising atoothed disc on the lower end of the plunger unit and the teeth of saiddisc having circumferential interfitting engagement with said internalprojections of the container.
 10. The structure of claim 9, and saidinternal projections comprising a plurality of circumferentiallyequidistantly spaced teeth-like projections in the bore of the containerneck substantially at the mouth of said neck.
 11. The structure of claim8, and said push button element comprising a depressed concave plateelement having a conical periphery, said cap having a conical boreportion opening through its top and forming a seat for said push buttonelement.
 12. The structure of claim 1, and said closure cap having anannular lateral shoulder above the screw-threads of the cap adapted toabut the open end of the container when the cap is completely engagedtherewith.
 13. The structure of claim 2, and said first means comprisinga disc on the plunger unit movable therewith and having axial movingengagement with an interior part of the closure cap, and the secondmeans comprising a transverse member on the lower end of the plungerunit and extending into the neck of the container and being rotatableand axially movable therein when disengaged from said internalprojections.
 14. The structure of claim 13, and said closure capincluding an elevated crown portion above the mouth of said containerforming a housing for said disc and said spring, said spring bearing onthe bottom of said disc and urging said plunger unit outwardly relativeto the container mouth.
 15. The structure of claim 14, and a cup elementin the interioR of said crown portion and secured therein againstrotation and having a splined bore slidably receiving the disc for axialmovement, the cup element having a bottom wall forming a support for oneend of said spring, and a seal carried by the plunger unit and havingsealing engagement with said bottom wall when the plunger unit is in itsnormal outward position under the biasing influence of said spring.